Multifunctional PDA@Ti3C2Tx/PU coatings with integrated anti-icing, anti-corrosion, and photothermally triggered self-healing performance for metal protection

Polar equipment is prone to icing and metal corrosion in harsh environments such as low temperature, high humidity and high salt. It is urgent to develop multifunctional coatings with anti-icing, anti-corrosion and self-healing functions. In this paper, PDA@Ti 3 C 2 T x composites were prepared by oxidative self-assembly of polydopamine (PDA) on the surface of Ti 3 C 2 T x , and their catechol/amino groups were used to enhance interfacial adhesion and photothermal conversion properties. A flexible polyurethane (PU) matrix was constructed using hexamethylene diisocyanate (HDI), polydimethylsiloxane (PDMS), 2, 5-bis (aminomethyl) furan and bismaleimide (BMI) as raw materials, and a high interfacial compatibility composite coating (PUKT) was prepared by chemical bonding of PDA@Ti 3 C 2 T x with PU through 3-aminopropyltriethoxysilane (KH550). The freezing time of water droplets on the surface of the coating was 208 s longer than that of pure PU, and the ice layer could fall off within 325 s under 0.5 sun illumination. Electrochemical impedance spectroscopy and relaxation time distribution analysis show that the coating can effectively block the penetration of corrosive media at room temperature and low temperature, and the strong bonding between the two-dimensional lamellar structure and the substrate further improves the corrosion resistance. In addition, the coating relies on the Diels-Alder reversible reaction network to achieve efficient damage self-healing under photothermal triggering, giving it long-term protection. This study provides a new integrated coating strategy with anti-icing, anti-corrosion and self-healing functions for metal protection in polar environment. • PDA enhanced the stability and photothermal properties of Ti 3 C 2 T x . • The PDA@Ti 3 C 2 T x /PU composite coating with high compatibility was formed by covalent bonding. • At −20 °C, the PUKT coating removes ice in 290 s. • The coatings before and after scratching can protect the metal from corrosion for a long time at 4 °C. • The coating can achieve self-healing within 300 s due to its efficient photothermal conversion efficiency.